Backport upstream commit to Ubuntu 15.10 (Wily) SRU stream

[bugproxy]

== Comment: #0 - UMA KRISHNAN <email address hidden> - 2015-11-18 16:27:06 ==
---Problem Description---
When FC login times out, cxlflash resets the link. As part of reset, when the link comes back up, cxlflash driver calls scsi_scan_host() and in case previous scan is still running we get the message and stack dump on console/logs.

scsi host2: scsi_prep_async_scan called twice
CPU: 16 PID: 55 Comm: kworker/16:1 Not tainted 4.2.0-439-f9a408a+ #1
Workqueue: events cxlflash_worker_thread [cxlflash]
Call Trace:
[c00000078bea7ae0] [c000000000a6e720] dump_stack+0x90/0xbc (unreliable)
[c00000078bea7b10] [c0000000006f539c] scsi_scan_host+0x28c/0x2a0
[c00000078bea7bb0] [d000000004085344] cxlflash_worker_thread+0x144/0x430 [cxlflash]
[c00000078bea7c50] [c0000000000d8b64] process_one_work+0x1a4/0x4c0
[c00000078bea7ce0] [c0000000000d9014] worker_thread+0x194/0x5f0
[c00000078bea7d80] [c0000000000e1630] kthread+0x110/0x130
[c00000078bea7e30] [c000000000009530] ret_from_kernel_thread+0x5c/0xac
cxlflash 0009:00:00.0: cxlflash_async_err_irq: FC Port 1 -> login succeeded, fc_status 0x114001D80000F

This message is alarming to customers. Community has already fixed this. We would like to see the upstreamed commit a4cf30e15ccea82a07fa5870e8af787b9ea1a672 (scsi_scan: don't dump trace when scsi_prep_async_scan() is called twice) backported to Ubuntu 15.10 (Wily) SRU stream.

---uname output---
Linux tul83p1 4.2.0-444-5b49ef1+ #1 SMP Wed Nov 18 12:44:21 CST 2015 ppc64le ppc64le ppc64le GNU/Linux

Machine Type = 8286-42A

---Debugger---
A debugger is not configured

---Steps to Reproduce---
 Simply disconnecting the adapter and plugging it back in, triggers this scenario.

Contact Information = <email address hidden>

Stack trace output:
 no

Oops output:
 no

System Dump Info:
  The system is not configured to capture a system dump.

*Additional Instructions for <email address hidden>:
-Attach sysctl -a output output to the bug.

[Brad Figg (brad-figg)]

This bug is awaiting verification that the kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-wily' to 'verification-done-wily'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[bugproxy (bugproxy)]

------- Comment From <email address hidden> 2015-12-16 06:54 EDT-------
Externalising the comment from UMA KRISHNAN

I have tested the proposed wily kernel and I see the bug to be resolved. I will change the state to verification-done-wily

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux - 4.2.0-21.25

---------------
linux (4.2.0-21.25) wily; urgency=low

  [ Luis Henriques ]

  * Release Tracking Bug
    - LP: #1522108

  [ Upstream Kernel Changes ]

  * staging/dgnc: fix info leak in ioctl
    - LP: #1509565
    - CVE-2015-7885
  * [media] media/vivid-osd: fix info leak in ioctl
    - LP: #1509564
    - CVE-2015-7884
  * KEYS: Fix race between key destruction and finding a keyring by name
    - LP: #1508856
    - CVE-2015-7872
  * KEYS: Fix crash when attempt to garbage collect an uninstantiated
    keyring
    - LP: #1508856
    - CVE-2015-7872
  * KEYS: Don't permit request_key() to construct a new keyring
    - LP: #1508856
    - CVE-2015-7872
  * isdn_ppp: Add checks for allocation failure in isdn_ppp_open()
    - LP: #1508329
    - CVE-2015-7799
  * ppp, slip: Validate VJ compression slot parameters completely
    - LP: #1508329
    - CVE-2015-7799

linux (4.2.0-20.24) wily; urgency=low

  [ Brad Figg ]

  * Release Tracking Bug
    - LP: #1521753

  [ Andy Whitcroft ]

  * [Tests] gcc-multilib does not exist on ppc64el
    - LP: #1515541

  [ Joseph Salisbury ]

  * SAUCE: scsi_sysfs: protect against double execution of
    __scsi_remove_device()
    - LP: #1509029

  [ Manoj Kumar ]

  * SAUCE: (noup) cxlflash: Fix to escalate LINK_RESET also on port 1
    - LP: #1513583

  [ Matthew R. Ochs ]

  * SAUCE: (noup) cxlflash: Fix to avoid virtual LUN failover failure
    - LP: #1513583

  [ Oren Givon ]

  * SAUCE: (noup) iwlwifi: Add new PCI IDs for the 8260 series
    - LP: #1517375

  [ Seth Forshee ]

  * [Config] CONFIG_DRM_AMDGPU_CIK=n
    - LP: #1510405

  [ Upstream Kernel Changes ]

  * net/mlx5e: Disable VLAN filter in promiscuous mode
    - LP: #1514861
  * drivers: net: xgene: fix RGMII 10/100Mb mode
    - LP: #1433290
  * HID: rmi: Disable scanning if the device is not a wake source
    - LP: #1515503
  * HID: rmi: Set F01 interrupt enable register when not set
    - LP: #1515503
  * net/mlx5e: Ethtool link speed setting fixes
    - LP: #1517919
  * scsi_scan: don't dump trace when scsi_prep_async_scan() is called twice
    - LP: #1517942
  * x86/ioapic: Disable interrupts when re-routing legacy IRQs
    - LP: #1508593
  * xhci: Workaround to get Intel xHCI reset working more reliably
  * megaraid_sas: Do not use PAGE_SIZE for max_sectors
    - LP: #1475166
  * net: usb: cdc_ether: add Dell DW5580 as a mobile broadband adapter
    - LP: #1513847
  * KVM: svm: unconditionally intercept #DB
    - LP: #1520184
    - CVE-2015-8104

 -- Luis Henriques <email address hidden> Wed, 02 Dec 2015 17:30:58 +0000